I. Field of the Invention
The present invention relates generally to the field of load retention more particularly to a power screw load retention system.
II. Description of the Related Art
FIG. 1A illustrates one type of a prior art vehicle transport trailer 100. Several vehicles 105 can be transported on the trailer. Each of the vechicles typically has its own platform 110 onto which each vehicle 105 is secured.
FIGS. 1B-1C illustrate prior art vehicle trailer tie down systems. As previously described, each vehicle 105 is secured to its platform 110. FIG. 1B illustrates the vehicle 105 tied to its platform 110 by chains 115 in a xe2x80x9cVxe2x80x9d arrangement. FIG. 1C illustrates the vehicle 105 tied to its platform by chains 115 in an xe2x80x9cAxe2x80x9d arrangement. The vehicle 105 is typically restrained to the platform 100, and therefore the trailer, by connecting the chains 115 to the frame of the vehicle 105 and the platform 110 or other part of the trailer. The chains 115 are placed in tension to prevent movement. The chains 115 are tightened in opposite directions to prevent the vehicle 105 from shifting front to back or vice versa. Currently, locking mechanisms 120 are used to keep the chain 115 from loosening due to forces acting upon the vehicle 105 (e.g. gravity, centripetal and other forces asserted on the vehicle 105 from the trailer or otherwise). There are many types of mechanisms 120 such as ratcheting and clamping devices that are typically manually tightened by the operator of the trailer. The chain 115 also may be routed around idlers 125 or the tightening mechanism 120 has to be relocated in order to achieve sufficient tension in the chain 110 in the correct direction to properly secure the vehicle 105.
The operator of the truck that hauls the trailer is typically responsible for tightening the vehicles into place. This process requires the operator to tighten chains 115 on each of the four corners of each car.
In general, the invention features a power screw load retention system that uses hydraulics to automatically and securely attach a vehicle to a transport trailer. The power screw load retention system can be used to tie down any load securely to a trailer or other structure. This system provides even tensions on all tie down locations of the vehicles being transported and thus prevents undue stresses on the vehicles.
In general, in one aspect, the invention features a power screw apparatus, including an elongated channel, a power source located on one end of the channel, a shaft connected to the power source and in threaded engagement with a carriage, the carriage adapted to translate along the channel and an end cap located on a side of the channel opposite the power source.
In an implementation, the apparatus further includes a link connected to the carriage, the link protruding from a longitudinal opening located on an upper surface of the channel and running a portion of the length of the channel.
In another implementation, the apparatus includes a rod located within the carriage and substantially perpendicular to the shaft, the rod adapted to hold the link within the carriage.
In another implementation, the link is adapted to connect to a connecting member such as a chain, strap or rope.
In another implementation, the end cap is coupled to the shaft.
In another implementation, the shaft includes an anti-backdriving thread profile.
In still another implementation, the apparatus includes a bearing support located at a fixed location within the channel between the carriage and the power source and a shaft coupling connected between the shaft and the power source and positioned within the bearing support, wherein the bearing support includes a first substantially rectangular holder located on one side on the shaft coupling, a second substantially rectangular holder located on the other side of the shaft coupling, wherein the first and second holders are substantially perpendicular to the shaft and positioned within the channel and a mounting flange located between the power source and the shaft coupling.
In yet another implementation, the power source is hydraulic.
In another aspect, the invention features a powerscrew load retention system, including a platform having a frame and one or more surfaces adapted to receive a load, wherein the platform includes a plurality of power screw sections having a load retention power screw apparatus, each apparatus including an elongated channel, a power source located on one end of the channel, a shaft connected to the power source and in threaded engagement with a carriage, the carriage adapted to translate along the channel and an end cap located on a side of the channel opposite the power source.
In an implementation, one surface of the frame is a first surface on a first side of the frame and another surface is a second surface on a second side of the frame, substantially parallel to and in the same plane as the first surface.
In another implementation, the system further includes a first line located adjacent the first surface that is parallel to a second line located adjacent the second surface, wherein a first and second power screw section are aligned with the first line and a third and fourth power screw section are aligned with the second line.
In still another implementation, the power source of the first power screw section is adjacent and coupled to the power source of the second power screw section, and wherein the power source of the third power screw section is adjacent and coupled to the power source of the fourth power screw section.
In yet another implementation, the carriage of the first section and the carriage of the second section are adapted to translate toward one another and away from one another, and the carriage of the third section and the carriage of the fourth section are adapted to translate toward one another and away from one another.
In still another implementation, the invention features a vehicle transporter including a plurality of platforms adapted to receive a vehicle, each of the platforms having a plurality of load retention screw apparatuses, each apparatus including an elongated channel, a power source located on one end of the channel, a shaft connected to the power source and in threaded engagement with a carriage having a link protruding from a longitudinal opening located along a top surface of the channel, the carriage adapted to translate along the channel and an end cap located on a side of the channel opposite the power source.
In an implementation, the transporter further includes a connecting member connected to the link of each carriage, each connecting member adapted to connect to the vehicle.
In another implementation, the transporter further includes flippers connected to the platform, the flippers adapted to load the vehicle onto the platform.
In another implementation, the flippers include idlers adapted to re-route the connecting members from the link to the vehicle.
In another implementation, the power sources are connected to a central control unit.
One advantage of the invention is that it reduces or eliminates the need for additional tightening/locking mechanisms to prevent the chains from loosening.
Another advantage is that it reduces the time it takes for the operator of the transporter to secure the vehicles to the transporter.
Another advantage is that it reduces the need for idlers. It also removes the need to relocate any tightening mechanisms to achieve sufficient tension in the chain in the correct direction to properly secure the load.
Another advantage is that the required length of the chains can be reduced and the system provides a more even distribution of the chain loads on all four positions reducing the risk of damage to the vehicle.
Other objects, advantages and capabilities of the invention will become apparent from the following description taken in conjunction with the accompanying drawings showing the preferred embodiment of the invention.